Magnetic Bonding Pads for Precise Wafer and Die Alignment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The semiconductor industry faces challenges in achieving precise alignment and reducing misalignment during the bonding of semiconductor dies, which affects device performance and yield due to the shrinking size of electronic components.
Innovation Solution
The use of magnetic bonding pads that are attracted to each other by magnetic force during the bonding process, aligning them accurately and improving the alignment of wafers or dies, thereby enhancing surface area contact and reducing resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional bonding methods are used, then bonding process is simple, but alignment precision deteriorates due to misalignment during bonding
Solution Approach 1:
Magnetic bonding pads are introduced as intermediary elements between the bonding surfaces. These pads generate magnetic fields that act as mediators to attract and align the bonding pads of opposing wafers, thereby achieving precise alignment without requiring complex mechanical positioning systems
Solution Approach 2:
The patent replaces mechanical alignment systems with magnetic field-based alignment. Instead of using complex mechanical positioning and alignment mechanisms, the invention uses magnetic attraction forces between magnetized bonding pads to automatically align the wafers during the bonding process
2Manufacturing precision
If magnetic bonding pads are used, then alignment precision is improved, but device complexity increases due to additional magnetic components
Solution Approach 1:
The magnetic bonding pads combine multiple functions into a single component: they serve as both the bonding interface and the magnetic field source. By merging the bonding function with the alignment function in one integrated pad structure, the patent avoids adding separate magnetic alignment mechanisms that would increase device complexity
Solution Approach 2:
The magnetic bonding pads are designed to perform multiple functions simultaneously: providing mechanical bonding contact, generating magnetic fields for alignment, and serving as electrical connection points. This multi-functionality reduces the need for additional specialized components
3Productivity
If feature size is reduced, then integration density is improved, but alignment difficulty increases due to smaller tolerances
Solution Approach 1:
The magnetic bonding pads enable self-alignment of the wafers during bonding. The magnetic attraction forces automatically pull the bonding pads into alignment without requiring external positioning systems or complex alignment procedures, which is particularly beneficial for maintaining precision as feature sizes decrease
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The magnetic bonding technique improves alignment, increases surface area contact, and enhances device performance and yield by reducing misalignment and resistance in semiconductor bonding processes.
Implementation Method 1
magnetic bonding pads that are attracted to each other by magnetic force during the bonding process
Data Source
AI summary
A method includes forming first bonding pads over a first substrate, wherein the first bonding pads include a layer of ferromagnetic material, wherein each first bonding pad produces a respective magnetic field having a first orientation; and bonding second bonding pads to the first bonding pads using metal-to-metal bonding.